Barman tours clubs with a European bunch of boozers (7)
I believe the answer is:
bacchae
'bunch of boozers' is the definition.
(participants in Roman festival Bacchanalia)
'barman tours clubs with a european' is the wordplay.
'barman' becomes 'bach' (Bach, a composer responsible for bars of music).
'tours' is an insertion indicator.
'clubs' becomes 'c' (abbreviation used in card games such as bridge).
'with' means one lot of letters go next to another.
'european' becomes 'e' (abbreviation e.g. EU).
'bach' placed around 'c' is 'bacch'.
'bacch'+'a'+'e'='BACCHAE'
(Another definition for bacchae that I've seen is " The --, tragedy by Euripedes".)